<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script>
        var arr = [2, 6, 1, 7, 4];
        var sum = 0;
        for (var i = 0; i < arr.length; i++) {
            sum += arr[i];
        }
        var ave = sum / arr.length;
        console.log(sum, ave);

        var arr1 = [2, 6, 1, 77, 52, 25, 7];
        var max = 0;
        for (var i = 0; i < arr1.length; i++) {
            max = max > arr1[i] ? max : arr1[i];
        }
        console.log(max);

        var arr2 = ['red', 'green', 'blue', 'pink'];
        var str = '';
        for (var i = 0; i < arr2.length; i++) {
            str += arr2[i] + '|';
        }
        console.log(str);
    </script>
</head>

<body>

</body>

</html>